# Carpentry Calculators

The carpentry calculators on mycarpentry.com are online tools you can use to simplify everyday construction calculations. They were designed for builders and carpenters constructing multi-level structures and can also be helpful to homeowners building a deck or patio cover onto their homes.

## Carpentry Calculators

**Stair Calculator** - The Stair Calculator calculates stair rise and run, stair rail angle, stringer length, step height, tread depth, and the number of steps a stair stringer. There are two flavors: **automatic** and **manual**.

**Roof Pitch Calculator** - The Roof Pitch Calculator calculates the roof pitch, slope, angle, and length of Common Rafters (in inches or millimeters) and displays the calculated results on a rafter profile diagram.

**Arch Calculator** - The Arch Calculator calculates the position of the *focus points* of an ellipse, based on the height and length of an ellipse, to determine the curve of an arch. Use the results to layout and build an archway using instructions available on mycarpentry.com.

**Cubic Yard Calculator** - The Cubic Yard Calculator calculates the volume of a three-dimensional space in cubic yards and cubic feet. This calculator can also calculate the yards of concrete required for a patio slab or deck footing.

## Math Calculators

These math calculators add additional functionality to the construction calculators above.

**Acre Calculator** - converts acres to square miles, square feet, and square yards. It also does the reverse for each of the four area measurements. The results are in square meters and hectares. This calculator is most useful when you need to convert the size of large areas, like lots and acreage, into different area values.

**Square Root Calculator** - calculates the square root of a given number and provides the results in both decimal and fraction format. The fraction format makes this a helpful calculator for carpentry projects.

**Fraction Calculator** - converts a decimal value to a fraction to the lowest common denominator.

## Stair Calculators - Automatic and Manual

The **Automatic Stair Calculator** requires only one manual input field, *Total Rise*. It calculates the stringer based on the Total Rise and three other pre-selected values. The **Manual Stair Calculator** allows more flexibility; you control the Total Rise, Total Run, and the Number of Steps on the stringer; the calculator does the rest.

**Stair Calculator (Metric)** - The Metric (millimeters) version of the stair calculator provides the same automatic and manual features as the Imperial (inches) version.

If one of these calculators doesn't fit your particular need, visit our Carpentry Math page to learn about some of the formulas used in carpentry. Learn how mycarpentry.com uses the Pythagorean Theorem to calculate stairs, determine rafter length, and square the walls of a structure.

If you need to determine the maximum span of a wood structural member, visit Span Tables for information on the allowable lengths of joists and rafters. The three tables available are ceiling joist span table, floor joist span table, and rafter span table.

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